Answer:
Metals are malleable : They can be bent and shaped without breaking. This is because they consist of layers of atoms that can slide over one another when the metal is bent, hammered or pressed.
Explanation:
Pure iron is a bright silvery white metal which oxidizes (rusts) rapidly in moist air or in water containing dissolved oxygen. It is soft, malleable, and ductile, and is strongly magnetic (ferromagnetic).
What kind of force acts within a molecule?
OA. A nonpolar force
OB. A Van der Waals force
OC. An intermolecular force
OD. An intramolecular force
The forces that act within a molecule are intramolecular forces.
What is intramolecular force?The forces that will be generated within a molecule between its atoms will be called the intramolecular force, these are mainly ionic and covalent bonds. These forces are the ones that must be overcome in order to generate a chemical change within the molecule and are the ones that determine what its chemical properties are within a substance.
Ionic bond is in which the complete transfer of electrons occurs and there is a large difference in electronegativity between the atoms, while in the covalent bond the electrons are shared between the two atoms and their electronegativities are similar.
Therefore, we can confirm that the forces that act within a molecule are intramolecular forces.
To learn more about intramolecular forces visit: https://brainly.com/question/12783802
#SPJ1
The diagram below shows the different phase transitions that occur in matter.
Which arrow would most likely represent the phase change that involves the same amount of energy as arrow 1?
A material changes physically when its state changes. They don't involve any alterations to the matter's chemical composition and are reversible. State changes that occur frequently include melting, freezing, sublimation, deposition, condensation, and vaporization.
Which arrow would most likely represent the phase change that involves the same amount of energy as arrow 1?
"Arrow 4."
The energy required to go from a liquid to a gas is equivalent to that required to go from a gas to a liquid.
The process by which a substance transforms from the liquid phase to the gaseous state is known as boiling.
Diagram of water in phase:
Water changes from a liquid to a gas through the phase-shifting process of evaporation (water vapor).
Water changes its state from a gas to a liquid during the phase shift process known as condensation, and the resulting vapor turns into a cloud.
To know more about Matter, click on the link below:
https://brainly.com/question/17011982
#SPJ9
Answer: arrow 4
Explanation: just took the test ;-)
Which of the following is an example of how financial goals change due to a value shift?
O buying a new wallet due to wear and tear to your current wallet
O moving from the city to suburbs after having children
O replacing a new phone after losing your old phone
O selling your old computer online to have funds for a new computers
Buying a new wallet due to wear and tear to your current wallet is referred to an example of how financial goals change due to a value shift and is denoted as option A.
What is Value shift?This is defined as the movement between the positive and negative values along a global spectrum of value and is usually dependent on different types of factors.
In this scenario, a torn wallet as a result of wear and tear means it has a negative value and having financial goals to buy a new one is referred to as the most appropriate choice.
Read more about Financial goals here https://brainly.com/question/2801397
#SPJ1
Answer: Moving from the city to suburbs after having children.
Explanation:
1) Once you start saving money, what can be your next step toward financial stability?
Investing it in a wise manner
2) Why is it important to track your income and your expenses?
Because knowing whether you can afford your lifestyle or not is the 1st goal of financial literacy
3) As you grow older, which of these might make you change your personal finance decisions more?
Your family priorities
4) Which showed you finance 1st?
Your needs
5) Which of the following is an example of how financial goals change due to value shift?
Moving from the city to suburbs after having children
6) Which expense is a spending want?
Movie tickets
7) Which options show a financial goal? Select the 2 correct answers
Paying off a credit card & saving for college
8) Which is a common way to spend money from your bank to a bank in a different country?
Wire transfer
9) How can you deposit a paper check?
A & C
10) What is typically included in COGS?
All of the answers are correct
11) What is typically considered part of SG&? Slect the 2 correct answers
Billing cost & commissions
12) What is another term for income statement?
profit and loss (P&L) statement
13) What is another name for an emergency fund?
A rainy day fund
14) What is defined as a budget surplus?
Take-home pay exceeds spending
15) Is using 401(K) money in an emergency the best idea?
No, early withdrawal of 401(K) money will incur a penalty
just took the Earning and Spending Unit Test.
15 POINTS!!!!! NEED ASAP!!!
1. Describe the differences between scale and proportion in relation to a scientific model.
2. In your own words, describe why scientific models are useful, even though much of the time their scale or proportions are not accurate when compared to the real thing.
3. Describe how atoms can be mostly empty space, even though they are the building blocks of everything in the universe. (i.e. how can your desk be made of atoms which are mostly empty space if it is solid?)
4. We learned about three different types of graphs. Describe each type of graph briefly, including what data goes where, then input a picture example of each type of graph.
Line Graph
Bar Graph
Circle Graph
Scale is the 'size of one object and proportion refers to the size of the parts of an object, scientific models help you visualize, atoms do not contain any empty space, they are filled completely with spread-out electrons, circle graph shows percentages and line graphs show data over time'
1. Scale and proportion are both design elements that have to do with size scale is the size of one object in relation to the other objects in a design or artwork and proportion refers to the size of the parts of an object in relationship to other parts of the same object.
2. Scientific models are useful models can help you visualize, or picture in your mind, something that is difficult to see or understand and models can help scientists communicate their ideas and also understand processes and make predictions that's why time their scale or proportions are not accurate when compared to the real thing.
3. Atoms do not contain any empty space and they are filled completely with spread-out electrons, making the shrinking of atoms impossible that's why it is said that the building blocks of everything in the universe.
4.Circle graph shows percentages and line graphs show data over time and bar graphs are for comparing data collected by counting and line graph is graph that uses lines to connect individual data point this three are graph are important
Know more about scale and proportion
https://brainly.com/question/13553546
#SPJ1
Answer it please! I just need an example
Answer:
Sorry what is you question? If it is about the length of the lego piece, then then length is approximately 3.7 cm.
Explanation:
What is the mass in grams of 0.05 moles of gold?
The mass of 0.05 mole of gold is 9.85 grams.
Equation :The following equation relates the mass and molar mass of a substance to its mole:
Mole = mass /molar mass
We can determine the mass of gold using the formula above. This is attainable as follows:
0.05 mole = gold in one mole.
Molar mass of gold = 196.97 g/mol
Mole = mass / molar mass
0.05 = mass / 196.97
Mass = 0.05 × 196.97
Mass of gold = 9.85 g
Hence, the mass of the gold is 9.85 g.
Definition of mass :A physical body's mass is its total amount of matter. Additionally, it is a gauge of the body's inertia, or resistance to acceleration in the face of a net force The gravitational pull an object has on other bodies is also influenced by its mass. The kilogram is the fundamental unit of mass in the SI.
To know more about gravitational pull :
https://brainly.com/question/13467280
#SPJ9
A __________ is a flowing, moving stream of water that feeds into a body of water.
hill
plain
plateau
river
Answer:
River
Explanation:
What type of reaction is shown below?
CaCO3(s)→ Cao(s) + CO₂(g)
O A. Decomposition
OB. Single-displacement
O C. Double-displacement
OD. Combustion
Insulin is biological molecule that regulates glucose levels in the human body.
Its chemical formula is C256H387N65079S6
Determine the percent composition of one of the elements of insulin. (25 points)
Show your work. (25 points)
Reveal the element chosen in the subject line. (25 points)
Share your % composition with a classmate that determined the % composition of a different element (25 points)
Insulin is a protein composed of chains, an a series with 21 amino acids and a B chain with 30 amino acids which are related together by using sulfur atoms. Insulin is derived from a seventy four-amino-acid prohormone molecule referred to as proinsulin.
The primary reason of insulin is to regulate the body's power deliver via balancing micronutrient stages throughout food intake 30. Insulin is crucial for transporting intracellular glucose to insulin-based mobile tissues together with the liver, muscle, and adipose tissue.
Insulin facilitates preserve blood sugar levels inside regular limits. It does this by means of taking glucose from the bloodstream and transporting it to the body's cells. Cells use glucose for strength and shop excess inside the liver, muscle, and adipose tissue.
Insulin offers cells with glucose for strength via reducing the frame's blood sugar levels and helping cells take in glucose. whilst blood sugar is too low, the pancreas releases glucagon.
Learn more about Insulin here:-https://brainly.com/question/786474
#SPJ9
Total # of molecules in 2ZnSO4?
12.044x10^23 molecules in 2ZnSO4
as it is seen there are 2 moles in zinc sulphate
To find no of molecules in 2 moles of zinc sulphate
=no of moles × no of avogadro number
= 2×6.02214x10^23
= 12.044x10^23 molecules
A "mole" is the quantity of a material that is precisely 6.02214076 X 1023 particles in the International System of Units. The particles might be molecules, ions, or atoms.The term "mole," which can alternatively be spelt "mol," refers to a typical scientific unit of measurement in chemistry used to calculate large quantities of extremely small things like electrons, molecules, or other specified items. The Avogadro's Number (6.02214076 X 1023), which is constant for any element or set of particles, defines the mole as an extraordinarily enormous number of units. The International System of Units chose this value as the mole definition (SI)To know more about mole
visit : https://brainly.com/question/26416088
#SPJ9
A sample of metal has a mass of 20.27 g, and a volume of 4.89mL. What is the density of this metal
4145.19 g/L is the density of this metal.
A ratio of an object's mass to volume can be used to determine its density. Mass per unit volume is the measurement unit as a result.
From a physicist's point of view, mass can be described as a measurement of the quantity that is inside a body, omitting elements like the object's volume and any forces that might be exerting pressure on it.
The volume of an object is a measure of how much space it takes up in three dimensions.
ρ = m ÷ V (Density is Mass divided by Volume)
Learn more about density here:
https://brainly.com/question/15164682
#SPJ9
What is the value of secant theta given the diagram below?
Answer:
The value of sec theta is
How to determine the value of sec theta
From the diagram, we start by calculating the length of the hypotenuse (h).
So, we have:
Evaluate
Simplify
The value of the secant in the second quadrant is calculated as:
So, we have:
Evaluate
Hence, the value of sec theta is
Read more about trigonometry at:
brainly.com/question/11967894
THANKS
11
5.0
(6 votes)
Explanation:
hope it helps
Match the type of mechanical waves to images of particle motion. In each case, the wave moves from left to right.
Image 1 - Surface wave
Image 2 - Longitudinal wave
Image 3 - Transverse wave
What is a wave?The term wave refers to a disturbance along a medium that transfers energy. We know that a transverse wave is one in which the direction of wave motion is perpendicular to that of the disturbance. This occurs in a water wave.
The Longitudinal wave is one in which the direction of the wave motion is parallel that of the disturbance. This is common in a spiral spring. A surface wave could be seen during an earthquake occurrence.
Let us now match the waves;
Image 1 - Surface wave
Image 2 - Longitudinal wave
Image 3 - Transverse wave
Learn more about waves:https://brainly.com/question/3639648
#SPJ1
What is the mass of the oxygen
used during the reaction?
Iron + Oxygen → Iron Oxide
Iron
19.43 g
Iron Oxide
20.91 g
Give your answer to the correct number of
significant figures.
Mass of Oxygen (g)
The mass of the oxygen used during the reaction is 8.16 g
The reaction is given as ,
4Fe + 3[tex]O_{2}[/tex] → 2[tex]Fe_{2} O_{3}[/tex]
The molar ratio of the above reaction = 4:3
It means four moles of Fe react with 3 moles of oxygen molecule to form Iron Oxide .
mole of iron = given mass / molar mass = 19.43 g / 55.845 g/mole = 0.34 mole
If four moles of Fe react with 3 moles of oxygen molecule to form Iron Oxide .
The number of moles of oxygen = 3 moles × 0.34 mole / 4 moles = 0.22 mole
The number of moles of oxygen = given mass / molar mass = 0.22 mole
The number of moles of oxygen = given mass / 32= 0.22 mole
given mass = 0.22 × 32 = 8.16 g
to learn more about oxygen
https://brainly.com/question/13370320
#SPJ1
Answer: The answer is 1.48
Explanation:
ionic equation for the reaction between aqueous solution of potassium carbonate and dilute sulphuric acid
Answer:
Ionic equation for the reaction of Potassium Carbonate (aqueous) with dilute Sulphuric Acid gives Potassium Sulphate, Carbon Dioxide and Water.
What is ionic equation?
Ionic equations are chemical equations that represent the electrolytes in aqueous solution as dissociated ions, similar to molecular equations which express compounds as molecules. Usually, this is a salt that has been dissolved in water; in the equation, the ionic species are denoted by (aq) to denote that they are in aqueous solution.
Complete balanced chemical equation is given below:
K₂CO₃ (aq) + H₂SO₄ → K₂SO₄ (aq) + CO₂ + H₂O
To know more about ionic equation and chemical reactions, click on this link
https://brainly.com/question/16243859
#SPJ9
Calculate the kilojoules needed to heat 221 g of gold from 18 ∘C to 195 ∘C . Express your answer to three significant figures and include the appropriate units.
231 g of gold need to be heated from 18 °C to 195 °C in 5.27 kJ of heat.
The amount of heat, or Q, is what we want to know. To do this, we would apply the formula Q = m•C•T. The beginning and final temperatures can be used to calculate the m, C, and T. We start with 231 g of gold that is 18 °C and add heat to raise the temperature to 195 °C. We can use the following expression to determine how much heat is needed.
Q = c*m*Δt
Q: where the heat
c: The gold's specific heat capacity (0.129 J/g.°C)
m: mass
T: Alteration in temperature
Q=0.213 J/g C x 231 g x (195-18)
=5.27 x 1000 J
=5.27 kJ
231 g of gold need to be heated from 18 °C to 195 °C in 5.27 kJ of heat.
Learn more about heat here-
https://brainly.com/question/1429452
#SPJ9
ANSWER ASAP FORF BRAINLIEST!!!!!
For this and the following two questions, determine the density of a substance (in g/dL) of a sample with a mass of 8.3 x 10-1 dag and a volume of 4.10 mL. What is the right-most significant figure after performing the calculation in scientific notation?
The density of a substance (in g/dL) of a sample with a mass of 8.3 x 10-¹ dag and a volume of 4.10 mL is 202.44g/dL.
How to calculate density?The density of a substance is the measure of the mass of matter contained by a unit volume.
The density of a substance can be calculated by dividing the mass of the substance by its volume.
According to this question, a substance with a mass of 8.3 x 10-¹ dag has a volume of 4.10 mL. The density can be calculated as follows:
1 dag = 10g0.83 dag = 8.3g 1 millilitre = 0.01 decilitre4.10millitre = 0.041 deciliterDensity = 8.3g ÷ 0.041dL
Density = 202.44g/dL
Therefore, the density of a substance (in g/dL) of a sample with a mass of 8.3 x 10-¹ dag and a volume of 4.10 mL is 202.44g/dL.
Learn more about density at: https://brainly.com/question/21461758
#SPJ1
The mass unit associated with density is usually grams. If the volume (in mL or cm3 ) is multiplied by the density ( g/mL or g/cm3 ) the volume units will cancel out, leaving only the mass units. Keep in mind that the volume and density must use the same volume unit for the cancellation.
If a large marshmallow has a volume of 2.75 in3 and density of 0.242 g/cm3 , how much would it weigh in grams? 1 in3=16.39 cm3 .
The mass of the marshmallow is 10.9 g.
What is the relationship between mass, volume and density of a substance?The mass of a substance is the quantity of matter present in that substance.
The volume of a substance is the amount of space a given mass of that substance occupies.
The density of a substance is the ratio of the mass and a given volume of that substance.
Therefore, the relationship between mass, volume and density is given below as:
Density = mass/ volumeFrom the data provided:
volume of the marshmallow = 2.75 in³
1 inch³ = 16.39 cm³
volume in cm³ = 16.39 * 2.75
volume of the marshmallow = 45.07 cm³
density of the marshmallow = 0.242 g/cm³
Mass of the marshmallow = volume × density
Mass of the marshmallow = 0.242 g/cm³ * 45.07 cm³
Mass of the marshmallow = 10.9 g
Learn more about mass, volume and density at: https://brainly.com/question/952755
#SPJ1
What is the oxidation state on Ec in the formula below? Ec4O2
The oxidation state on Ec in the given chemical compound Ec₄O₂ is determined as +1.
What is oxidation state?
The oxidation number or oxidation state, is the total number of electrons that an atom either gains or loses in order to form a chemical bond with another atom.
The given compound;
= Ec₄O₂
The oxidation state of Ec is calculated as follows;
let the oxidation state = x
4x + (2 x -2) = 0
4x - 4 = 0
4x = +4
divide both sides of the equation by "4"
4x/4 = +4/4
x = +1
Thus, the oxidation state on Ec in the given chemical compound Ec₄O₂ is determined as +1.
Learn more about oxidation state here: https://brainly.com/question/14426389
#SPJ1
. 2.514g Ca, 1.004g O empirical formula
The empirical formula of the given compound is [tex]CaO[/tex].
A chemical compound's empirical formula in chemistry is the simplest whole number ratio of atoms within a molecule.
Given:
Mass of Ca = 2.514g
Mass of O = 1.004g
Molar mass of Ca = 40.078g/mol
Molar mass of O = 15.999g/mol
To find:
Empirical formula = ?
Formula:
Empirical formula = Moles of Ca : Moles of O
Calculations:
No. of moles of Ca = 2.514 / 40.078
n of Ca = 0.06273 moles
No. of moles of O = 1.004 / 15.999
n of O = 0.06275 moles
Divide both by the lowest no. of moles
n of Ca : n of O = 1 : 1
Empirical formula = [tex]CaO[/tex]
Result:
[tex]CaO[/tex] is the empirical formula of the compound.
The complete question is:
In an experiment, a 2.514 g sample of calcium was heated in a pure stream of oxygen, and was found to increase in mass by 1.004 g. Calculate the empirical formula for the given compound.
Learn more about empirical formula here:
https://brainly.com/question/14044066
#SPJ9
Select the statement that accurately summarizes how heat energy spreads throughout a substance. A) As a particle is heated, it absorbs energy. As it bumps into a nearby particle, it transfers all of the heat energy to the second particle. This leaves the first particle with no energy, so its movement slows.B) Heated particles absorb the energy and begin to move more and faster. As they move around, they bump into nearby particles and transfer some of their energy to those particles. This continues until all of the particles in the substance have the same amount of energy. C)Particles are heated and move around. They transfer thermal energy to the other particles as they bump into each other. This continues until all the particles lose all of their energy and motion stops. D)When particles are heated, they become sluggish and slow down. They transfer energy to nearby particles causing them to slow down, too.
The statement " Heated particles absorb the energy and begin to move more and faster. As they move around, they bump into nearby particles and transfer some of their energy to those particles. This continues until all of the particles in the substance have the same amount of energy " summarises the heat transfer throughout the substance.
Heat is the thermal energy that is transferred from a system to its environment or from one thing to another. The object with the higher temperature is transferring energy to the thing with the lower temperature.In order to move thermal energy from one thing or thing to another, or from a system to its surroundings, there are three possible methods:ConductionConvectionRadiation The energy of the particles increases when energy is transmitted to an object. This indicates that the particles have higher kinetic energy, which causes them to move and vibrate more fastly. As the particles move more fastly, they "bump" into nearby particles and transfer some of their energy with them. In this manner, the substance at the other end receives the energy.This is how energy is transferred in a substance.
Learn more about heat transfer here:
https://brainly.com/question/16055406
#SPJ9
Rank each of the following elements by the common number of single bonds the element makes when it bears no formal charge. Each element is from
the second row of the periodic table F,O,N,C,NE
In this ranking we would have; C > N > O > F > Ne.
What is the formal charge?The term formal charge has to do with the charge that an atom appears to have in compound. We can obtain the formal charge from the formula;
Formal charge = [# of valence electrons] – [electrons in lone pairs + 1/2 the number of bonding electrons]
Let us now consider the atoms; F, O, N, C, Ne. We have to rank the atoms by the common number of single bonds the element makes when it bears no formal charge.
In this ranking we would have; C > N > O > F > Ne.
Learn more about formal charges:https://brainly.com/question/11723212
#SPJ1
A hamster in a ball begins its journey 5 feet to the left of a refrigerator, travels 20 feet to the right of the refrigerator, and
ends its journey directly in front of the refrigerator.
If negative values are assigned to positions to the left of its starting position and positive values are assigned to positions
to the right of its starting position, what is the displacement of the hamster?
(1 point)
O 5 feet
O-5 feet
O 0 feet
O 20 feet
The displacement of the hamster ball is equal to -5 feet. Therefore, option (B) is correct.
What is displacement?The displacement of an object can be demonstrated as the change in the position of an object. The displacement can be defined as the minimum length between the initial and the final point of an object.
The displacement can be defined as a vector quantity posses both direction of displacement and magnitude. Therefore, the measurement of the displacement of an object includes direction.
The S.I. unit of the displacement meters and the C.G.S. unit are centimeters the same as the distance.
A hamster in a ball starts its journey 5 feet to the left of a refrigerator, travels 20 feet to the right of the refrigerator, and ends its journey in front of the refrigerator.
Therefore, the displacement of the hamster ball is equal to -5 feet.
Learn more about displacement, here:
brainly.com/question/14422259
#SPJ1
Name two branches of Chemistry and give an example for each of what that branch has offered to society.
biomedical; kidney function testing, blood testing (healthcare)
analytical; water and soil testing (provides well balanced nutrition for us)
How do you find the volume of an irregularly shaped object?
Fill a beaker with water half full. Take note of the original line. Drop the object in. Note the displacement of the water. Subtract the New water level by the old water level. This is volume.
Iron, carbon, and phosphorus are elements found in the periodic table. Tests involving these three elements would show that at normal room temperature
If you take a 13.0- mL portion of the stock solution and dilute it to a total volume of 0.650 L , what will be the concentration of the final solution?
To make a stock solution, weigh out the proper amount of a pure solid or measure out the proper amount of a pure liquid, put it in the right flask, and then dilute it to the desired volume. Depending on the intended concentration unit, many methods can be used to measure the reagent.
If you take a 13.0- mL portion of the stock solution and dilute it to a total volume of 0.650 L , what will be the concentration of the final solution?
"The final solution's concentration would be 0.26M."
By adding extra solvent, you are lowering the concentration of the stock solution in the issue (This process is known as dilution).
Since you increased the volume of the fluid from 13 to 650 milliliters, it was diluted:
50 times = 650 mL / 13 mL
We must now take the concentration of the stock solution in order to determine the concentration of a final solution.
If the standard solution is 13M, then
The final solution's concentration would be 13M / 50 = 0.26M.
To know more about stock solution and final solution, click on the link below:
https://brainly.com/question/20316955
#SPJ9
Which statement about exoplanets is true?(1 point)
Responses
They only appear once before they disappear in space.
They only appear once before they disappear in space.
They are discovered when they dim a star they pass by.
They are discovered when they dim a star they pass by.
They are objects that are no longer considered planets.
They are objects that are no longer considered planets.
They can be detected by ordinary telescop
They are discovered when they dim a star they pass by ' is true statement about exoplanets among all .
So , B is correct option .
In our solar system, every planet revolves around the Sun. Exoplanets are planets that revolve around other stars . Exoplanets are extremely difficult to directly observe using telescopes. The intense light from the stars they orbit obscures them .
Therefore, astronomers employ various techniques to find and research these far-off planets. By observing the impacts that these planets have on the stars they circle, astronomers look for exoplanets.
to Learn more about exoplanets please click here ,
https://brainly.com/question/21880131
#SPJ1
Question 4.1Write the equilibrium constant expression,Kc , for the following reaction:
(If either the numerator or denominator is 1, please enter 1.)
See attachment for question
equilibrium constant expression, Kc ,for the following reaction: Kc for the Reaction is: 1 / [Fe⁺³]² [S⁻²]³
What is Equilibrium Constant of a Reaction ?The equilibrium constant is a type of chemical reaction (usually denoted as the symbol K) use to give the relationship between the products and reactants when a chemical reaction reaches to it's equilibrium. Such as the equilibrium constant of concentration (marked as Kc) of a chemical reaction at equilibrium is defined as the ratio of the concentration of products to that of the concentration of the reactants.It is important for us to note that there are various different types of equilibrium constants which provides relationship between products and the reactants of equilibrium reactions in variety of units.For a chemical reaction, the equilibrium constant is defined as the ratio between the part of reactant and that of product which is generally used in order to determine the chemical behavior.Given Reaction and it's equilibrium constant is:
2Fe⁺³(aq) + 3S⁻²(aq) ⇄ Fe₂S₃ (s)
Now Equilibrium Constant of the reaction is: [Fe₂S₃] / [Fe⁺³]² [S⁻²]³
We know that concentration of solid compound is 1.
Hence, Kc for the Reaction is: 1 / [Fe⁺³]² [S⁻²]³
Thus, from the above conclusion we can say that, Kc for the Reaction is: 1 / [Fe⁺³]² [S⁻²]³ .
Learn more about Equilibrium Constant here: https://brainly.com/question/3159758
#SPJ9
A baseball is pitched to the batter,
What is the motion of the reference